UC San Diego

The prevalence of coral diseases has significantly surged in the past couple of years, particularly within the Caribbean region. Notably, certain corals exhibiting resistance harbor symbiotic bacteria, suggesting a potential role of these microorganisms in bolstering resilience. In this study, I explored four strains of symbiotic bacteria, hypothesizing their capability to produce antibiotic compounds targeting coral pathogens. Through culturing these bacteria and evaluating their extracts, we found that only Glutamicibacter soli displayed inhibitory effects, although without complete pathogen eradication. Further chemical analysis of G.soli culture extracts unveiled the presence of two prominent molecules: cholic acid and a previously undescribed aromatic compound: N-[2-(4-Hydroxyphenyl)ethyl]-3-methylbutanamide. The isolation of cholic acid stands out as a unique finding, shedding light on its origin within marine bacterial extracts and expanding our understanding of symbiotic interactions in coral health.